Public Class Diskettes

    Private Sub btntotal_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btntotal.Click
        Dim total As String
        Dim disks As Double

        disks = txtinput.Text

        If disks <= 0 Then
            txttotal.Text = "You have to order at least 1 diskette"
        ElseIf disks >= 100 Then
            total = disks * 0.2
            txttotal.Text = "The total is " + FormatCurrency(total)
        Else
            total = disks * 0.25
            txttotal.Text = "The total is " + FormatCurrency(total)
        End If
    End Sub
End Class